Update URLs and set redirects for "build" links to "map" pattern step

[javabster]

The build section is being renamed to "Map problem to circuits", the url should be updated accordingly and redirects set up.

Question: how verbose should we make the url? I'm open to either of the following options:

• /map-problem-to-circuits/page-name
• /map/page-name
• some other option?

[Eric-Arellano]

Replaced by #1297